1. Field
The invention relates to means for automatically selecting a channel from a plurality of channels in an electronic apparatus, and particularly to a test control board which performs time shared access to, and selection of, a channel or channels of a multichannel audio tape recorder for alignment, azimuth, record bias, equalization, etc., adjustment purposes.
2. Prior Art
A requirement for successfully operating an apparatus having a plurality of channels is that the multiple heads, channels, record circuits, etc., be aligned, adjusted, etc., i.e., be properly operative. To perform such channel alignments and adjustments, an operator may apply a test signal to the input of a channel while monitoring the output thereof. Heretofore, access to the channels was made via the back of the apparatus, and it was necessary to manually connect a conductor to the input and to the output of each channel to be tested. Obviously, in an apparatus with many channels, i.e., 16, 24, etc., such a procedure is time consuming, cumbersome and totally inefficient.
More recently, a switching system has been used in audio tape recorders, wherein a test circuit includes a jack which allows coupling an external test circuit to the inputs of all the channels of the recorder. However, the outputs of the channels must be manually individually connected and disconnected at the back of the recorder. Thus the system fails to provide an automatic, logic oriented, channel selection system capable of any flexibility in rapidly connecting an external test circuit to one or more inputs, while selectively coupling an associated external monitoring circuit to any output, of one or more given channels.